Within minutes of Jack’s talk I began to wonder, “Does this guy know who we are?” Because I coach nervous professionals on how to present in smart, strategic ways, I’m used to dealing with jittery neophytes. However, it had been a long time since I attended a presentation by a supposed seasoned pro who truly bombed.

It happens to the best of us. In reflecting on Jack’s talk, I was most struck by how he made the most basic speaking mistakes. He reminded me why those mistakes are so basic.

Here are the 12 most basic speaking blunders that will turn off an audience:

1. Fail to establish credibility.

Jack was not introduced by anyone in the wedding industry. He introduced himself by giving us his resume—which didn’t contain a connection to the wedding industry. He had no story that could assure us he knew who we were as a professional group.

2. Dress inappropriately.

Jack wore a standard blue suit and red tie that made him look uncomfortable and too much like a salesman. Am I nit-picking? Sure. But because he failed to connect with us through a story, his clothes enhanced his overall appearance as an outsider who wasn’t clued-in to who we were.

3. Use a schoolmarm tone.

After arousing our suspicions that he had little understanding of who we were as an audience, he began to recite statistics about the U.S. wedding industry. He presented canned information most of us already knew in a tone that made me feel like I was in a classroom. He didn’t grasp that we were seasoned pros at the top of our game.

4. Manhandle the mic.

The microphone was on a stand. When Jack spoke, he tended to move away from the stand, which meant his voice frequently dropped out. Those in the back of the room had a hard time hearing him.

5. Fumble with the PowerPoint.

Jack got off to a shaky start, and when he couldn’t smoothly transition from slide to slide, he rapidly lost our trust in his competence. He became distracted, thrown off balance and had difficulty talking to us.

6. Turn your back on the audience.

At one point there was a major glitch with the laptop. Jack focused on fixing the tech problem (even though there was a tech guy nearby), turned his back on us and stopped talking. We all started talking with each other—about him!

7. Presume your co-presenter is prepared.

Jack co-presented with a tech guy whose job was to explain the site’s technical gaming innovations. However, the tech guy failed to clearly set up the concept of the website’s game. People quickly felt lost, and asked questions tinged with annoyance. His abstract answers did not smooth over our concerns.

8. Play video of someone more engaging than you.

At one point, Jack played a video from the website’s founder. While the video was polished, it added two problems. First, the founder was more engaging than Jack. Second, the founder lives in Ireland and said nothing to make us believe he understood the American wedding market.

9. Avoid answering questions directly.

Jack had an agenda, and was determined to stick to it. He spun all of his answers to the purposes of that agenda.

10. Make lame jokes.

Jack’s jokes were at the expense of his younger, better-looking tech colleague. He aimed the jokes at the women in the audience (the majority), but he didn’t realize the group’s collective sense of humor was more sophisticated than his jokes.

11. Insult potential buyers.

Jack explained that the website’s vendor page does not list photographers and videographers separately. It lumps them together under the “captured memories” heading. When a videographer pointed out that what he does is different from a photographer, Jack dismissed him with, “It’s all visuals.” Ouch!

12. Offer no way to follow up.

Jack ended by thanking us, and said he hoped we’d consider joining this new and exciting wedding community. But he didn’t give us any information about how we could join and if we could get a special introductory rate for attending the talk. Twenty-four hours later, I couldn’t describe in one sentence what Jack’s talk was about.

Jack is not the only person to bomb big time. We’ve all been there. Still, I’ve wondered why the talk crumbled the way it did.

I now realize Jack’s biggest mistake was that he focused on selling a product, not forging a relationship with a new demographic—high-end wedding professionals. He wanted to impress rather than connect. It only makes sense that he made so many basic presentation mistakes.

Every audience member silently asks the presenter, “Do you see me? Do you know what I need?” Mistakes abound when we forget competence is rooted in seeing the customer. People leave a winning presentation feeling that the presenter understood them and offered them something worthwhile.

Jack made me re-examine my presentation style and reflect on where I’ve become sloppy. What about you? What can you do to reassure audience members that you see them?